1. Field of the invention
This invention relates to a novel composition having etching resist properties, a pattern forming method making use of the composition, a printed-wiring board and a process for producing the printed-wiring board.
More particularly, this invention is concerned with printed-wiring board processing in which, in forming a copper printed-wiring pattern, a resist pattern for etching a copper-clad laminate is directly drawn on copper foil by ink-jet printing.
2. Related Background Art
In conventional subtractive processes used in printed-wiring board processing, wiring patterns are formed by preparing pattern films by means of a laser plotter in accordance with wiring pattern data outputted from a CAD (computer-aided design system), and etching copper foil by using a resist ink or a dry film resist.
In such conventional processes, it is necessary to first form a pattern film, and to prepare a printing plate in the case when a resist ink is used or to take the steps of lamination, exposure and development in the case when a dry film resist is used.
Such methods currently used can be said to be a method in which the digitized wiring data are returned to an analogic image forming step. Screen printing has a limit to work size because of the printing precision of the plate. The dry film process is a photographic process and, though promising a high precision, requires many steps, inevitably resulting in a reasonably high cost especially for the manufacture in small lot.